简介：Inthispaper,weprovetheglobalexistenceoftheweaksolutiontotheviscousquantumNavier-Stokes-Landau-Lifshitz-Maxwellequationsintwo-dimensionforlargedata.ThemaintechniquesaretheFaedo-Galerkinapproximationandweakcompactnesstheory.

简介：RuO_2nanoparticlessupportedonmulti-walledcarbonnanotubes(CNTs)functionalizedwithoxygen(OCNTs)andnitrogen(NCNTs)wereemployedfortheoxygenevolutionreaction(OER)in0.1MKOH.Thecatalystsweresynthesizedbymetal-organicchemicalvapordepositionusingrutheniumcarbonyl(Ru_3(CO)_(12))asRuprecursor.TheobtainedRuO_2/OCNTandRuO_2/NCNTcompositeswerecharacterizedusingTEM,H_2-TPR,XRDandXPSinorderprobestructure–activitycorrelations,particularly,theeffectofthedifferentsurfacefunctionalgroupsontheelectrochemicalOERperformance.TheelectrocatalyticactivityandstabilityofthecatalystswithmeanRuO_2particlesizesof13–14nmwasevaluatedbylinearsweepvoltammetry,cyclicvoltammetry,andchronopotentiometry,showingthatthegenerationofnitrogen-containingfunctionalgroupsonCNTswasbeneficialforbothOERactivityandstability.InthepresenceofRuO_2,carboncorrosionwasfoundtobesignificantlylesssevere.

简介：借助于超几何函数，在广义非中心X2分布级数形式密度函数表达式的基础上列出了两类具体椭球等高分布下的广义非中心X2分布密度函数的精确表达，并给出了详细的证明过程；同时计算了这两类具体椭球等高分布下的广义非中心X2分布对应高阶矩的形式，作为推论验证了非中心X2分布相关的结论．

简介：Inthispaper,wepresenttheluminescentpropertiesofTm3+∕Ho3+co-dopednewglass.Aseriesofsilicategermanateglasswaspreparedbytheconventionalmelt-quenchingmethod.IntheTm3+∕Ho3+co-dopedsilicategermanateglass,astrongemissionof2μmoriginatingfromtheHo3+:5I7→5I8transitioncanbeobservedunderconventional808nmpumping.Thecharacteristictemperatures,structure,andabsorptionspectrahavebeenmeasured.TheradiativepropertiesofHo3+inthepreparedglasswerecalculated.TheemissioncrosssectionofHo3+ionstransitioncanreach4.78×10-21cm2around2μm,andtheFWHMisashighas153nm.TheenergytransferefficiencybetweenHo3+andTm3+hasalargevalue（52%）,whichindicatestheTm3+∕Ho3+co-dopedsilicategermanateglassisasuitablecandidateforthe2μmlaser.Moreover,theenergytransfermechanismbetweenTm3+andHo3+ionswasinvestigated.

简介：采用油的酸的一条简单solvothermal途径被开发了与不同形状准备锐钛矿TiO2nanocrystals，它被从0～0.5mmol增加NaF的数量从nanorods调节到nano椭圆体，并且光乐队差距因此从3.47eV减少了到3.29eV。不管多么当氟化物被改变到NH4F，结果的TiO2nanocrystals拥有了一个锐钛矿阶段，但是由小尺寸的nanocrystals组成并且nanorods，和乐队差距被增加到3.53eV。X光检查光电子光谱学(XPS)结果与NaF的增加的数量说明了氟的符号内容的增加为形状和光乐队的变化的报道能TiO2nanocrystals豁开。而且，氟的符号内容的缺席引起了形状的更少的变化，产品的光乐队差距的增加面对NH4F。这结果可以提供另一个方法与氟化物的帮助改变形状和金属氧化物nanocrystals的乐队差距。

简介：采用EDTA络合滴定法测定选铁尾矿中的氟化钙含量。选用稀乙酸浸取试样中的碳酸钙,分离过滤氟化钙,用锆-二甲酚橙褪色分光光度法测定浸取液中的氟含量,折算为在稀乙酸中微溶的氟化钙的量;同时沉淀部分用氯化铝溶液在沸水浴中溶解浸取氟化钙,以三乙醇胺掩蔽干扰离子,在KOH介质中,以钙指示剂为指示剂,用EDTA标准滴定溶液测定沉淀中氟化钙的量,两者之和为试样中氟化钙的含量。用此法对试样进行11次平行测定,相对标准偏差（RSD）小于1.0%。在选铁尾矿试样中加入萤石标准物质进行加标回收实验,加标回收率在99%-102%。方法流程短,操作简单。精密度和加标回收率均能满足要求。

简介：采用CCSD（T）/aug-cc-pVTZ//MP2/aug-cc-pVTZ方法构建了HO2＋NO反应的单、三重态反应势能剖面.研究结果表明,标题反应在单、三重态均存在3条反应通道,分别经抽氧、加成和抽氢反应生成产物NO2＋OH、HNO3和HNO＋O2.其中抽氧、加成反应的优势通道发生在单重态势能面上（通道R1和R2）,而抽氢的优势通道则发生在三重态势能面上（通道R6）.利用经典过渡态理论（TST）并结合Wigner矫正模型在200K1500K温度范围内计算了优势通道R1,R2和R6的速率常数kTST/W.结果显示,在计算温度范围内抽氧、加成反应的通道R1和R2始终存在竞争,且抽氢反应通道R6在高温区500K1500K竞争作用也逐渐显现,但抽氧通道R1分支比始终大于81%,具有绝对优势.

简介：Inthisstudy,nanocrystallineCo–Ni–MgferritepowderswithcompositionCo0.5Ni0.5-xMgxFe2O4aresuccessfullysynthesizedbytheco-precipitationmethod.Asystematicinvestigationonthestructural,morphologicalandmagneticpropertiesofun-dopedandMg-dopedCo–Niferritenanoparticlesiscarriedout.Thepreparedsamplesarecharacterizedusingx-raydiffraction（XRD）analysis,Fouriertransforminfraredspectroscopy（FTIR）,fieldemissionscanningelectronmicroscopy（FESEM）,andvibratingsamplemagnetometry（VSM）.TheXRDanalysesofthesynthesizedsamplesconfirmtheformationofsingle-phasecubicspinelstructureswithcrystallitesizesinarangeof32nmto36nm.ThelatticeconstantincreaseswithincreasingMgcontent.FESEMimagesshowthatthesynthesizedsamplesarehomogeneouswithauniformlydistributedgrain.TheresultsofIRspectroscopyanalysisindicatetheformationoffunctionalgroupsofspinelferriteintheco-precipitationprocess.ByincreasingMg2+substitution,roomtemperaturemagneticmeasurementshowsthatmaximummagnetizationandcoercivityincreasefrom57.35emu/gto61.49emu/gand603.26Oeto684.11Oe（1Oe=79.5775A·m-1）,respectively.ThehighervaluesofmagnetizationMsandMrsuggestthattheoptimumcompositionisCo0.5Ni0.4Mg0.1Fe2O4thatcanbeappliedtohigh-densityrecordingmediaandmicrowavedevices.

简介：Cobaltandnickelcomplexes(1a-1dand2a-2d,respectively)supportedby2-imidate-pyridineligandsweresynthesizedandusedfor1,3-butadienepolymerization.ThecomplexeswerecharacterizedbyIRandelementanalysis,andcomplex1awasfurthercharacterizedbysingle-crystalX-raydiffraction.Thesolidstatestructureofcomplex1adisplayedadistortedtetrahedralgeometry.Uponactivationwithethylaluminumsesquichloride(EASC),allthecomplexesshowedhighactivitiestoward1,3-butadienepolymerization.Thecobaltcomplexesproducedpolymerswithhighcis-1,4contentsandhighmolecularweights,whilethenickelcomplexesdisplayedlowcis-1,4selectivityandtheresultingpolymershadlowmolecularweights.Thecatalyticactivitiesofthecomplexeshighlydependedontheligandstructure.Withtheincrementofpolymerizationtemperature,thecis-1,4contentandthemolecularweightoftheresultingpolymerdecreased.

简介：Differentialabsorptionlidar(DIAL)isanexcellenttechnologyforatmosphericCO2detection.However,theaccuracyandstabilityofatransmittedon-linewavelengtharestrictlyrequiredinaDIALsystem.Thefluctuationofatunablepulsedlasersystemisrelativelymoreseriousthanthatofotherlasersources,andthisconditionleadstoalargemeasurementerrorforthelidarsignal.Theseconcernsposeasignificantchallengeinon-linewavelengthcalibration.Thisstudyproposesanalternativemethodbasedonwaveletmodulusmaximafortheaccurateon-linewavelengthcalibrationofapulsedlaser.Becauseofthedifferentpropagationcharacteristicsofthewavelettransformmodulusmaximabetweensignalandnoise,thesingularitiesofasignalcanbeobtainedbydetectionofthelocalmodulusmaximainthewavelettransformmaximumatfinescales.Simulatedanalysisshowsthatthemethodismoreaccuratethanthegeneralmethodsuchasquinticpolynomialfittingandcansteadilymaintainhighcalibrationprecisionatdifferentsignal-to-noiseratios(SNRs).Last,16groupsofrealexperimentswereconductedtoverifythesimulatedanalysis,whichshowsthattheproposedmethodisanalternativeforaccuratelycalibratinganon-linewavelength.Inaddition,theproposedmethodisabletosuppressnoisesintheprocessofwavelengthcalibration,whichgivesitanadvantageinaccurateon-linewavelengthcalibrationwithalowSNR.

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简介：研究了Na2EDTA标准滴定溶液测定锡阳极泥中铋的方法。探讨了锡阳极泥的溶样方式、滴定溶液酸度、滴定溶液温度、共存元素干扰、加标回收、方法的准确度与精密度。方法适用于锡阳极泥中5％～20％铋量的测定，尤其是铟量在0．1%及以上时，方法相对标准偏差（RSD）为0．55oA～1．4％，加标回收率为99．81％～101．3％。具有操作步骤简单、适用性广、分析结果重现性好与准确度高等优点。

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简介：WereportontheobservationofsubcycleinterferencesofelectronwavepacketsreleasedduringstrongfieldionizationofH2withcycle-shapedtwo-colorlaserfields.Withareactionmicroscopewemeasurethree-dimensionalmomentumdistributionsofphotoelectronscorrelatedwitheitherH2+orprotonswithindifferentenergyrangesgeneratedbydissociationofH2+.Werefertothesedifferenttypesofphotoelectronsaschannels.Ourresultsshowthatthesubcycleinterferencestructuresofelectronwavepacketsareverysensitivetothecycleshapeofthetwo-colorlaserfield.Weexplainthisbehaviorbythedependenceoftheionizationtimewithinanopticalcycleontheshapeofthelaserfieldcycle.Thesubcycleinterferencestructurescanbefurtherusedtoobtaininsightintothesubcycledynamicsofmoleculesduringstrongfieldinteraction.

简介：基于第一性原理，计算了MgSiP2的能带结构，结果显示压强减小了能带带隙值，部分电子有效质量随着压强增大而减小。费米能级附近电子态密度计算结果显示：随着压强的增大，价带顶电子态密度的斜率逐渐减小，而导带底电子态密度的斜率逐渐增加。结合半经典玻耳兹曼理论，分别计算了p型和《型MgSiP2的电导率与弛豫时间的比值、赛贝克系数以及功率因子与弛豫时间的比值。结果发现：压强所致部分电子有效质量的减小，提高了p型和.型MgSiP2的电导率，但在一定程度上降低了MgSiP2的赛贝克系数。在压强作用下，相对于n型MgSiP2，，型MgSiP2的电导率增加幅度更大，补偿了压强所致乡型MgSiP2赛贝克系数的降低，提高了型MgSiP2的功率因子，使其大于n型MgSiP2的对应值。计算结果表明，通过增大压强可以提高p型MgSiP2的热电性能，为实验制备具有良好热电性能MgSiP2提供了指导方案。

简介：poly包括的合成聚合物电解质(用户终端设备)(vinilydenefluoride-hexafluoro丙烯)，PVDF-co-HFP和锌triflate，Zn(CF3有改变ZrO2nanofillers的集中的3)2被与N扔技术的答案因此准备，N-dimethylformamide(DMF)作为普通溶剂。有特别作文的聚合物电解质标本75wt%PVDF-co-HFP：7wt%ZrO2显示出的25wt%ZnTf+4.6的最高的传导性??????????????€潰祬???????畃????猯灵？？

简介：ThisstudyshowsthepreparationofaTiO_2coatedPt/C(TiO_2/Pt/C)byatomiclayerdeposition(ALD),andtheexaminationofthepossibilityforTiO_2/Pt/Ctobeusedasadurablecathodecatalystinpolymerelectrolytefuelcells(PEFCs).CyclicvoltammetryresultsrevealedthatTiO_2/Pt/Ccatalystwhichhas2nmprotectivelayershowedsimilaractivityfortheoxygenreductionreactioncomparedtoPt/Ccatalystsandtheyalsohadgooddurability.TiO_2/Pt/Cpreparedby10ALDcyclesdegraded70%after2000Accelerateddegradationtest,whilePt/Ccorroded92%inthesameconditions.TiO_2ultrathinlayerbyALDisabletoachieveagoodbalancebetweenthedurabilityandactivity,leadingtoTiO_2/Pt/CasapromisingcathodecatalystforPEFCs.ThemechanismoftheTiO_2protectivelayerusedtopreventthedegradationofPt/Cisdiscussed.

简介：Chemicalloopingdryreforming（CLDR）isaninnovativetechnologyforCO2utilizationusingthechemicalloopingprinciple.TheCLDRprocessconsistsofthreestages,i.e.CH4reduction,CO2reforming,andairoxidation.Spinelnickelferrite（NiFe2O4）waspreparedanditsmulti-cycleperformanceasanoxygencarrierforCLDRwasexperimentallyinvestigated.X-raydiffraction（XRD）andLaserRamanspectroscopyshowedthatapurespinelcrystallinephase（NiFe2O4）wasobtainedbyaparallelflowco-precipitatingmethod.NiFe2O4wasreducedintoFe-Nialloyandwustite（FexO）duringtheCH4reductionprocess.SubsequentoxidationofthereducedoxygencarrierwasperformedwithCO2asanoxidanttoformanintermediatestate:amixtureofspinelNi1-xFe2+xO4,Fe2+yO4andmetallicNi.AndCOwasgeneratedinparallelduringthisstage.Approximate185mLofCOwasgeneratedfor1gspinelNiFe2O4inasinglecycle.TheintermediateoxygencarrierwasfullyoxidizedintheairoxidationstagetoformamixtureofNi1+xFe2-xO4andFe2O3.Althoughtheoriginalstateofoxygencarrier（NiFe2O4）wasnotfullyregeneratedandagglomerationwasobserved,agoodrecyclabilitywasshownin10successiveredoxcycles.更多还原

简介：众多B2C网站已建立起会员等级制度，并据此向买家提供价格折扣。但会员等级制模型仅考虑买家交易金额，无法全面反映买家在线购买历史（onlinepurchasehistory），故不能准确提供差异化折扣。针对上述问题，提出了一种面向B2C电子商务的差异化折扣模型，该模型包含能体现买家在线购买历史的交易、退单、推荐购买、晒单等四个指标，将买家在线购买历史聚合为一个综合值，进而通过min-max标准化方法进行线性转换，将转换后的聚合值与会员等级基准折扣结合得到最终的差异化折扣，从而使得B2C网站可向同级别会员实施更精准的一对一营销和价格歧视策略。以京东商城为背景的仿真实验结果证明了本文新模型的有效性。

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